<table>
  <tr>
    <td>Arrays to threshold</td>
    <td>
      <select id="thresholdArray">
        <option value="sine wave">sine wave</option>
        <option value="x">x</option>
        <option value="y">y</option>
        <option value="z">z</option>
      </select>
    </td>
  </tr>
  <tr>
    <td>Operation</td>
    <td>
      <select id="thresholdOperation">
        <option value="Above">&lt;</option>
        <option value="Below">&gt;</option>
      </select>
    </td>
  </tr>
  <tr>
    <td>Treshold value</td>
    <td>
      <input id="thresholdValue" type="number" step="10" value="30" />
    </td>
  </tr>
</table>